Siemens is the ECU used in the 1*2s etc so thats right, but if you look for a V6 ECU is €99 iirc, its been a while since I've looked as its not something I require often!! My tuner is just used for diagnostics and abs/airbag work now
Either way don't let it put you off!! They are a fantastic bit of kit and can save you a lot of money in diagnostics if you decide to keep hold of it!!
Especially you decide to sell it on! Personally I'd keep it for the usefulness but if you wanna recoup the costs then sell it on bud! Be aware codes etc can take a while to arrive due to the time difference and Henk is based in the Philippines